If you want to use article associations between Seblod-articles you need a Joomla 3.x version and need to change the 'article association' field settings in the joomla language plugin.

Go to the plugin manager, then filter on 'language'... Click on System -- Language filter (make sure it is enabled)

Then go to the second tab 'Basic Options'

Set Item Associations on yes and save and close.

Then go to your Seblod Form and Content Type and add Article Association (JForm - Associations) to your admin fields. You can find it in the Joomla Article Base category.

Now you can add article associations for your multilanguage website.

Note: It won't work in the search and list view (i'm thinking about a way to achieve this)